The fringing-barrier reef lying to the east coast of Andros Island in the Bahamas represents the second largest reef complex in the western North Atlantic and is one of the most remote. The system extends for a distance of approximately 200 km (124 miles) from the Joulter Cays in the north to South Cay in the south. Based on the distribution, development, and architecture of reef communities within the vicinity of a mile off the coast, the reef may be divided into five major zones; the lagoon (including mangrove areas), back reef, reef crest, inner fore reef, and outer fore reef.

There are over One Hundred and Sixty-Four species of fish and coral that make up the coral reef community. These species are found in various densities along the reef.

The Andros Barrier Reef slopes down a vertical cliff that begins 20 m below the surface and then drops off to over 2000 m or 6,000 feet into a deep ocean trench called the Tongue of the Ocean. This vertical cliff or wall is facing the East and has great sun light penetration allowing for a vast amount of life to flourish along the wall. It also provides one of the most spectacular scuba diving experiences in the region.

The Andros Barrier Reef is famous for its deep water sponges and large schools of Red Snappers. It is the only place in the world where there is more than one Nassau Grouper Aggregation.

The Andros Barrier Reef segment is used as an example of the most perfect Atlantic Coral reef structure on display at the New York Natural History Museum.

Note: The Andros reef complex is not a true barrier reef system in the strict sense because of the relatively shallow depth of the lagoon and close proximity of the reef crest to the shoreline. It is also not a true fringing reef since it is not set directly against the shoreline. Hence, it is regarded as a hybrid in reef classification.